package com.imooc.ecommerce.advice;

import cn.hutool.core.util.ObjectUtil;
import com.imooc.ecommerce.annotation.IgnoreResponseAdvice;
import com.imooc.ecommerce.vo.CommonResponse;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;

/**
 * @author Mr.Ke
 * @create 2021-11-30-23:17
 * 实现统一响应
 */
@RestControllerAdvice(value = "com.imooc.ecommerce")
public class CommonResponseDataAdvice implements ResponseBodyAdvice<Object> {

    /** 判断是否需要对响应进行处理 */
    @Override
    public boolean supports(MethodParameter methodParameter, Class<? extends HttpMessageConverter<?>> aClass) {

        if (methodParameter.getDeclaringClass().isAnnotationPresent(IgnoreResponseAdvice.class)) {
            return false;
        }

        if (methodParameter.getMethod().isAnnotationPresent(IgnoreResponseAdvice.class)) {
            return false;
        }

        return true;
    }

  /**
   * @param o controller的响应
   * @param methodParameter
   * @param mediaType
   * @param aClass
   * @param serverHttpRequest
   * @param serverHttpResponse
   * @return
   */
    @Override
    @SuppressWarnings("all") // 屏蔽警告信息
    public Object beforeBodyWrite(Object o, MethodParameter methodParameter,
                                  MediaType mediaType, Class<? extends HttpMessageConverter<?>> aClass,
                                  ServerHttpRequest serverHttpRequest,
                                  ServerHttpResponse serverHttpResponse) {

        // 定义最终的返回对象
        CommonResponse<Object> response = new CommonResponse<>(0,"");

        if (ObjectUtil.isNull(o)) {
          return response;
        } else if (o instanceof CommonResponse) {
          response = (CommonResponse<Object>)o;
        } else {
          response.setData(o);
        }

        return response;

    }
}
